Just fill in your name and email address on the following fields for us to send you the invites. Your details will not be displayed publicly. Currently Google+ is under maintenance but we will try to send the invites as soon as Google+ comes up again.
Looks like the invite system will be more strict than it has given its beta users hours back. You may still want to place in your details and we will try to send you the invite the soonest. Our apologies.